A sample of $51$ mutual funds was taken and the mean return in the sample was $13\mathrm{.}5\%$ with a standard deviation of $8\mathrm{.}7\%.$ The return on a particular index of stocks $($against which the mutual funds are compared$)$ was $11\mathrm{.}6\%.$ When testing the hypothesis $($at the $10\%$ level of significance$)$ that the return on actively$-$managed mutual funds is higher than an index of stocks, what is the critical value? $($please round your answer to $2$ decimal places$)$